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چکیده
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Ceramic nozzles are unique options in the aerospace industry due to their ability to work at high temperatures . However, brittleness, structural defects, poor formability and complex methods for measuring their mechanical properties are obstacles to their development. In this study, four different conical nozzles were produced with Plasma Spray Forming (PSF) and since YSZ is one of the most common materials for high-temperature applications it was considered as the base material, and three YSZ alternatives, by changing the chemical composition (CYSZ), by changing the particle size (nanostructured YSZ), and by double layer architecture design, were investigated. Mechanical properties of conical nozzles were evaluated by the nanoindentation test using Oliver and Pharr method. This method can be quick and applicable the for mechanical properties evaluation of ceramic parts based on the load-depth curve. X-Ray diffraction (XRD) and scanning electron microscopy (SEM) were performed for the phase analysis and coating microstructure and porosities investigation. The results showed the promising features of nano-structured YSZ that are strongly based on the presence of nano-zones inside the coating structure.
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